Wright was examined by team doctors Thursday night at the Hospital for Special Surgery in Manhattan after experiencing lower-back pain. An MRI did not reveal any structural damage, the Mets said. Wright may resume baseball activity when the back pain subsides.
"It's a setback," general manager Sandy Alderson said. "We were happy that the MRI didn't show anything structural. There's no stress fracture. There's no stress reaction."
Alderson added that Wright has been prescribed anti-inflammatory medication for the next four to five days.
Wright, 32, originally departed an April 14 game against the Philadelphia Phillies with the hamstring strain. The Mets had hoped his rehab from the injury would last no more than three weeks, but Wright felt an issue with the muscle when he began to run full throttle and was backed off last week.
The Mets suggested Wright's hamstring currently is "doing very well."
Wright dealt with a stress fracture in his lower back during the 2011 season. He initially tried to play through the back discomfort, but ultimately landed on the disabled list for two months.
During Wright's current absence, the Mets initially tried using Eric Campbell at third base and Daniel Murphy at second base. With Campbell having slumped, team officials promoted prospect Dilson Herrera a week ago to man second base and moved Murphy to third base.
Manager Terry Collins spoke with Wright by telephone and expects him to resume baseball activity on Monday.
Collins said Wright had been prepared to enter a rehab game this Saturday before the back issue arose.
Wright wanted to get the back checked out because of the gravity of the 2011 stress fracture.
"It's not anything that's hugely major," Collins said.